1. Field of the Invention
The present invention relates in general to the field of information handling system circuit boards, and more particularly to a system and method for capacitive coupled via structures between circuit board ground, power and circuit planes.
2. Description of the Related Art
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
Over the past several decades, information handling systems have steadily increased their capacity to process and store information in designs having compact footprints. These improvements have been largely based on the availability of processors to handle greater numbers of computations with increased speed by fabricating increased numbers of circuits within a given size of semiconductor material. The processor designs have improved by increasing the number of cycles performed in a given time frame and decreasing the operating voltages. Improved processors allow more rapid execution of application instructions for interaction with an information handling system user as well as improved communication of information through busses that interface various components of an information handling system, such as memory, network interfaces and graphic display interfaces. Information handling system designers face a substantial challenge in interfacing the various components through a circuit board. For instance, design challenges include arranging components in a compact footprint with ease of assembly and adequate cooling. One type of circuit board-to-processor interface that has become increasingly common is the ball grid array (BGA) connector and socket. BGA sockets provide high density, high input/output count packaging with reduced pin-to-pin trace gaps by distributing the ball and grid connections between the processor and the circuit board.
One difficulty often faced in the design of information handling system circuit boards is that the speed, density and power requirements of powerful processors tend to generate undesired electromagnetic effects and interference. For instance, parasitic inductance is associated with the physical structure of integrated circuits. The parasitic inductance tends to disrupt power supply to the integrated circuit, especially at current flows having lower voltages and greater transient surges to meet the demands of powerful modern processors. Small parasitic effects have more pronounced effects on power delivery to processors, especially in transient conditions, as operating voltages decrease. Discrete component solutions are typically employed to reduce the undesired impact on power supply and delivery, such as associating capacitance with a power supply circuit board wire line to smooth current flow during transient power demands. However, the ability of discrete component solutions to compensate for power delivery, decoupling and processor package parasitic effects has fallen behind as processor density has increased and supply voltage decreased, especially in highly utilized areas of a circuit board such as near BGA socket connectors.